Gas burner and secondary air supply means



luly 2s, 1953 2,646,842

y n E. HANULr GAS BURNER vlAun; SxazcoNDA'iw AIR SUPPLY MEANS Haro/alLZ-2557@ mmymyw A TTONEYJ July 28, 1953 E. HANDLEY 25646,842 GAS mmmANn. ."sEouDARY AIR' sugeu MEANS l 'gsneets-sheet Filed Apil 11. .1949

BY l M wwf/M ATTORNEVJ Patented July 28, 1953 UNITED STATES PATENTOFFICE GAS BURNER AND SECONDARY AIR SUPPLY MEANS 2 Claims.

This invention relates to a gas burner and secondary air supply meansfor use in heating plants. In my Patent No. 2,295,784 I have disclosed aburner particularly adapted for use during the early and late part ofthe heating season which may be readily inserted in and removed from thedoor of an ordinary coal burning furnace.

It is an object of the present invention to provide an improved burnerof this character which is more economical to manufacture and moreeiiicient in operation and which can be used for year around heating.

Specifically, it is an object of the invention to reduce the cost of theburner head and of the mounting arrangements and the control devices.

It is also an object to provide a burner of this class which is moreeasily adapted to heating plants of all shapes and sizes.

A further object is to improve the combustion eiliciency of the burnerand particularly the flame distribution within the fire pot and thedelivery of secondary air to the flame.

Briefly, the invention consists of a burner head which is formed of twosheet-metal shells which are fastened together with the edges of theshells facing each other but spaced slightly apart to provide the gasflame openings. In some embodiments, these openings may be filled with aserpentine strip which increases port velocity and reduces the noise ofignition and extinction.

Other features and objects of the invention have to do with the detailsof construction and operation which will be set forth in the followingspecification and claims.

Figure 1 is a vertical sectional view of a burner in place in a furnaceand embodying a preferred form of the present invention.

Figure 2 is a top view of the burner in place.

Figure 3 is a View partly in section of an improved pressure regulatorand shut-ofi valve forming part of the burner assembly.

Figure 4 is a side elevation of a modified construction in whicha-serpentine insert strip is interposed between the edges of the shell.

Figure 5 is a plan view of the shell with a portion cut away to show theinsert.

Referring to the drawings, in Figure 1 there is shown a. furnace I0comprising the fire pot l2, grate I4 and fuel door opening I6. Theburner assembly, generally designated I8, mounts on a plate having ahorizontally pivoted upper section 22. The plates 20 and 22 abut thedoor opening and the unit is held in position by a door holder rod 24which is somewhat longer than the width of the fuel door opening I6. Achain 26 is secured to the rod 24 and has a screw-eye 28 by which themounting plate 25 may be tightly clamped in the position illustrated.Slidably secured to the closure plate 2i) is the curved circular mixturetube 30, the left-hand end of which pro-.- jects somewhat outside thedoor in a straight section 32 and the right-hand end of which carriesthe burner head 34. Surrounding the mixture tube 3B is a secondary airduct 36 of rectangular form which has a distribution box 38 by whichsecondary air is directed downwardly into the zone around the burnerhead 34.

The burner head 34 comprises two identical shell-shaped stampings 36 and38 which are joined together by a straight connector piece 40 at theleft-hand edge. This provides a narrow circumferential slot 42 throughwhich gas and air are delivered for combustion. The automatic pilot tube44 is also mounted 'on the door plate 20 within the secondary air duct36 and has a downwardly extending tip 46 adjacent the burner head 34.Mounted on the door plate 2@ is a gas inlet 48 which may be connected toa gas supply by a suitable conduit. The gas inlet feeds an automaticpressure control valve 59 which serves to maintain a constant outletpressure and feeds the gas orifice 52 through the automatic on-off valve54 The latter is controlled from the room thermostat in the usualmanner. Slidably mounted in the mixture tube end 32 is a telescopingmixer tube 54 having a slotted bracket 5E welded to the end there-of andcooperating with a set screw 58 on the bottom of the gas orifice xture52. The mixer tube 54 may be moved toward and away from the orifice 52and because of the relatively large diameter of the orifice fixture, theprimary air opening at the end of mixer tube 54 may be controlled by theproximity of the fixture 52 to the end of tube 54.

The gas regulator valve 55 is illustrated in detail in Figure 3 fromwhich it will be seen that the valve 60 cooperates with the seat 62 toopen or close communication with the inlet at the right and the outletat the left. The valve stem 64 is connected to a flexible diaphragm 65and carries a weight 68. The diaphragm is thus responsive to thepressure above the seat 52 which is outlet pressure and has a normaliiuctuation which serves to adjust the Valve 6B to whatever position isrequired to maintain the outlet pressure constant.

For the purpose of providing manually controlled shut-off of gas, thestem 64' is provided with a headed upward extension 'HJ which issurrounded by a small tube 12 slidable in the cover 14. The tube 'l2 hasa shoulder beneath the head of extension 19 and has a head 'it at itstop. A bell-crank lever 'I8 is pivoted at 85 on the cover lll and isconnected for manual actuation by a rod 82 which is pivotally connectedto the door section 22. A suitable spring and collar arrangement at 84provides a yielding connection to permit further movement of rod S2after valve 69 is tightly engaged with the seat 62. For furtherdisclosure of the details of the various elements of the burner such asthe automatic pilot and thermostatic control circuit, reference may behad to my above mentioned prior patent.

In operation, it will be seen that when the unit is to be inserted inthe furnace, the screw-eye 29 will be removed from the stationary doorplate 20 and the entire assembly inserted through the iire door openingI9 to position the plate 29 as shown. The access door 22 may be openedand the rod 24 and chain 26 placed in position and the screw-eye 28tightened to clamp the um't in place,

While the door E2 is open, the gas supply is shut off by reason of therod S2 having rotated the bell-crank 78 counterclocxwise to close thevalve E0. After the unit is secured in position, the pilot burner 46 maybe lighted and the access door 22 closed. If the room thermostat iscalling for heat this will open the automatic control valve 54 so thatgas is now delivered to the orince 52 because both valves 59 and 5t areopen. The mixture is accordingly deliv-ered to the burner head 34 whereit is ignited by the pilot i'lame.

The iiame produced by the burner head disclosed wipes the side walls ofthe combustion chamber and exchanges heat from the bottom s,

up. With the horizontal gas burning port, names and hot gases arenaturally sent in direction since they are projected toward the sidewalls and the natural tendency is for them to rise. In addition, theineffective heating surface at the front of the lire pot below the nredoor is not scrubbed with either flames or hot gases since in mostfurnaces there is little heating surface at this point. In the presentconstruction, secondary air is introduced at this point and passesdownwardly beneath the burner head 34 so that it may be introduced underthe iiame to assure proper aeration. It has been found that a much morestable combustion and higher eicency are produced by this construction.Furthermore, the burner operates over a much wider range of inputs andone size burner can cover the range previously requiring two differentsizes of burner.

In Figure 4, a modied construction is shown in which shells 90 aresupported by the usual mixture tube 39 and in which the edges 9i of theshells are spaced as shown in Figure 1. The shells 99 are similar tothose in Figure 1 in that they are circular and dished to provide aconcave-convex unit in which the concave sides are brought together inthe spaced relation above described. Approximately 75 degrees of thecircle at the back of the burner is closed at 92 by bringing the edges9i together and riveting the same. Also, at three other points 93 theedges of the rims 9| are brought together and riveted. In Figure 1, theconnecting plate i9 closes oi approximately 75 degrees of the circle ofthe plates 36. It is preferable that at least 270 degrees of open portbe provided in this type of burner. Interposed between the rims 9i is astrip 95 which is ilat at the portions 92 and 93 but which has aserpentine configuration between the spaced portions of rims 9i toprovide a plurality of radially extending ports 96. This serpentinestrip which creates these ports increases port velocity somewhat and hasbeen found to reduce the noise of ignition of the unit when heat iscalled for by controlling thermostat. Similarly, the noise of extinctionof the name is reduced. These are important factors in producing asatisfactory household unit.

This application is a continuation in part of my copending application,Serial No. 694,076, filed August 30, 1946, now Patent No. 2,490,127.

I claim:

l. In a gas burner conversion unit adapted for use in a solid fuelheating unit, a support, a mixture supply tube projectably mounted onsaid support to extend into the re box of said heating unit and curveddownwardly at its inner end, a burner head on the inner end of said tubehaving a closed circumferential portion and burner ports extendingcircumferentially about the remaining portion with axes directed awayfrom the supply tube, and in combination a secondary air supply tubesurrounding and mounted on said mixture supply tube and correspondinglyadjustably mounted with respect to said support7 said secondary air tubehaving an outlet extending downwardly around said curved portion of themixture tube with an opening at the closed circumferential portion ofthe burner head to project incoming secondary air below the burner onsaid mixture tube, said mixture tube and secondary air supply tube beingsimultaneously adjustable with respect to said support.

2. ln a gas burner conversion unit adapted for use ina solid fuelheating unit, a support, a ymixture supply tube projectably mounted onsaid support to extend into the fire box of said heating unit and curveddownwardly at its inner end, a burner head on the inner end of said tubecon prising a pair of oppositely facing shell members spaced apart toprovide a peripheral flame opening extending ciroumferentially throughat least 270 degrees, said shells being shaped to provide a closedperipheral portion at one place in the circumference, and in combinationa secondary air duct to extend into the fire box from said supportprojecting inward and downward and terminating in a downward, open-endportion at substantially the level of the burner head adjacent theclosed peripheral portion of the burner head where there is no flameopening whereby secondary air may be delivered beneath the burner head.

HAROLD E. EANDLEY.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 546,340 ORielly Sept. 17, 1895 842,792 Maohlet Jan. 29, 19071,385,509 Vance July 26, 1921 1,482,103 Van Daam Jan. 29, 1924 1,700,886Geurink Feb. 5, 1929 2,107,575 Matthews et al. Feb. 8, 1938 2,215,983Smith Sept. 24, 1940 2,297,856 Ames Oct. 6, 1942 2,487,959 Zink V. 15,1949 2,491,430 Tullis Dec. 13, 1949 2,498,162 Heller Feb. 2l, 19502,574,153 Meiners Nov. 6, 1951 FOREIGN PATENTS Number Country Date487,445 Great Britain June 2l, 1938

